aio: try to complete poll iocbs without context switch (1962da0d) · Commits · 戴 / test

fs/aio.c

+17 −3

Original line number	Original line	Diff line number	Diff line
	@@ -1633,6 +1633,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
	void *key)		void *key)
	{		{
	struct poll_iocb *req = container_of(wait, struct poll_iocb, wait);		struct poll_iocb *req = container_of(wait, struct poll_iocb, wait);
			struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll);
	struct file *file = req->file;		struct file *file = req->file;
	__poll_t mask = key_to_poll(key);		__poll_t mask = key_to_poll(key);

	@@ -1648,9 +1649,22 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,

	__aio_poll_remove(req);		__aio_poll_remove(req);

			/*
			* Try completing without a context switch if we can acquire ctx_lock
			* without spinning. Otherwise we need to defer to a workqueue to
			* avoid a deadlock due to the lock order.
			*/
			if (spin_trylock(&iocb->ki_ctx->ctx_lock)) {
			list_del_init(&iocb->ki_list);
			spin_unlock(&iocb->ki_ctx->ctx_lock);

			__aio_poll_complete(req, mask);
			} else {
	req->events = mask;		req->events = mask;
	INIT_WORK(&req->work, aio_poll_work);		INIT_WORK(&req->work, aio_poll_work);
	schedule_work(&req->work);		schedule_work(&req->work);
			}

	return 1;		return 1;
	}		}